69) Given the Following Reactions

69) Given the following reactions,

2PCl3(g) ⇌ 2P(g) + 3Cl2(g)Kc = 0.0667

PCl3(g) + Cl2(g) ⇌ PCl5(g)Kc = 4.0

calculate Kc for the reaction below.

2P(g) + 5Cl2(g) ⇌ 2PCl5(g)

A) 240

B) 1.1

C) 60

D) 23

Answer: A

61) Consider the following hypothetical equilibrium reaction:

A2(g) + B2(g) ⇌ 2AB(g) where Kc =

The equilibrium constant for the reaction: 2 A2(g) + 2 B2(g) ⇔ 4 AB(g) is ______.

A)

B) Kc4

C)

D)

E) Kc2

Answer: E

50) Consider the following reaction at a certain temperature.

2SO3(g) ⇌ 2SO2(g) + O2(g)

When the initial concentration of SO3(g) is 0.128 M, the concentration of oxygen gas at equilibrium is found to be 0.0130 M. Calculate Kc for this reaction.

A) 8.45 x 10-4

B) 1.62 x 10-2

C) 7.64 x 10-5

D) 1.47 x 10-3

Answer: A

Choose the Br∅nsted-Lowry acids and bases in the following equation:

HCN + OH-⇌ H2O + CN-

A) acids HCN, CN-bases OH-, H2O

B) acids CN-, OH-bases HCN, H2O

C) acids HCN, H2Obases OH-, CN-

D) acids OH-, H2Obases CN-, HCN

E) acids HCN, OH-bases H2O, CN-

Answer: C

Diff: 2 Type: MC

Reference: Section 16-2

21) Choose the Br∅nsted-Lowry acids and bases in the following equation:

NH4+ + OH-⇌ H2O + NH3

A) acids NH4+, OH-bases H2O, NH3

B) acids OH-, H2Obases NH3, NH4+

C) acids NH4+, OH-bases NH4+, H2O

D) acids NH4+, H2Obases OH-, NH3

E) acids NH4+, NH3bases OH-, H2O

Answer: D

Diff: 2 Type: MC

Reference: Section 16-2

30) 0.272 g of a monoprotic acid (Mw = 189 g/mol) is dissolved in water to produce 25.0 mL of a solution with pH = 4.93. Determine the ionization constant of the acid.

A) 4.1 × 10-8

B) 1.4 × 10-10

C) 2.1 × 10-4

D) 2.8 × 10-7

E) 2.4 × 10-9

Answer: E

41) Which of the following is a logical inference from the fact that a 0.10 molar solution of potassium acetate, KC2H3O2, is less alkaline than a 0.10 molar solution of potassium cyanide, KCN?

A) Hydrocyanic acid is a weaker acid than acetic acid.

B) Cyanides are less soluble than acetates.

C) Hydrocyanic acid is less soluble in water than acetic acid.

D) Acetic acid is a weaker acid than hydrocyanic acid.

E) 0.10 M potassium acetate is more concentrated than 0.10 M potassium cyanide.

Answer: A

Complete the following equation. List the conjugate acid base pairs. Put the base first in each pair.

HCl + NH3⇌

54) What is the [OH-] of a solution prepared by dissolving 0.0912 g of hydrogen chloride in sufficient pure water to prepare 250.0 ml of solution?

C) 10-12 M

70) The Kb value for methylamine is 4.2 × 10-4. What is the pH of an aqueous solution for which the label reads "0.042 M CH3NH2"?

A) 2.4

B) 4.8

C) 9.2

D) 11.6

E) 12.3

Answer: D

73) What is the concentration of free sulfate ion in a solution labeled "3.6M H2SO4"?

[Ka2 = 1.1 × 10-2]

A) 0.011 M

B) 0.040 M

C) 0.20 M

D) 0.60 M

E) 1.8 M

Answer: A

78) For the following compound, predict whether the solution is acidic, basic or neutral and why: NaC2H3O2.

List the following acids in order of increasing strength:

HBrOHIOHClO